I originally intended to experiment with new mounting and presentation techniques for mural-size prints. To that end, I made a series of 30×40″ prints for my own personal use, with the intent of sending them to a couple of service bureaus for mounting using different methods.

Since I planned to hang the prints on my own walls, I picked a few personal favorites I didn’t yet have on display. It was a mix of 4×5 film scans and digitally-captured images.

In the past, I subscribed to the common wisdom that up to a given print size the difference between digital files and film scans will be a wash but beyond a certain threshold, the large format scans will consistently have the upper hand. I was surprised to find (by my own subjective judgment) that this was not the case and in fact at this size some of the digital files actually produced sharper-looking prints.

This seems to contradict not only common perception but mathematical calculations (which I generally try not to argue with.) The explanation came to me as I was working on the files, preparing them for print. The raw 4×5 scans were indeed significantly larger but as anyone who worked with large scans knows, straight out of the scanner the files looks gritty; and lines, detail, and transitions appear a bit “fuzzy”. In comparison, a good digital capture, albeit containing less pixels, is very clean with clear detail and well-defined lines.

There is a difference between resolution and sharpness, the former being actual measurable detail and the latter being perceived/subjective appearance of detail. Until recently I thought they were well correlated but I’m no longer convinced.

At large print sizes, the digital files lend themselves well to interpolation while retaining the appearance of smooth lines and detail. The film scans, on the other hand, becomes fuzzier and harder to sharpen.

I now believe that rather than a clear threshold, there is an interim area where large format film still has sufficient detail and require little interpolation and can appear sharper than the digital capture but beyond that, where both formats require significant interpolation, the digital capture gives a sharper appearance despite having somewhat less detail.

In the coming few weeks I will ask friends who share my experience with various formats to evaluate these prints and see if they share my subjective impressions.

For now, though, I wouldn’t be too quick to assume that a large format scan will necessarily produce a better print. I will also think twice about the need for higher resolution digital capture (medium format or future camera upgrades).

This is one of the prints in the set. It is cropped from a file captured using a first-generation Canon 5D. To my eye (and surprise) it turned out to be the sharpest-looking print of the batch.